Interpreting the Sound Ratings of a Unit

Decibel (dB) Comparisons

Common Sounds

This decibel (dBA) table compares some common sounds and shows how they rank in potential harm to hearing. In many industries, workers are exposed to dangerous noise levels. This is particularly true in the construction, lumber, mining, steel and textile industries.

Since the sensitivity of the ear to sound is not the same for all frequencies, weighting or attenuating filters are included in the sound level meter's circuits to simulate the ears' response. A noise level meter gives an instantaneous measurement of the noise present, but cannot measure the duration of the exposure. To measure the amount of noise a person is exposed to over a period of time, a "dosimeter~ or an integrated sound level meter must be used. Sources for above include the American Medical Association and the Canadian Hearing Society of Ontario. Decibel table developed by the National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland 20892. January 1990.